The present invention relates to a novel weed growth inhibitor composition for a lawn grass and an upland farm, and a method for cultivation and management of a lawn grass.
In golf courses and so on, various lawn grasses, such as Japanese lawn grasses and American or European lawn grasses, are cultivated and managed, and their varieties are numerous. These lawn grasses have varying degrees of resistance to herbicides. Thus, if it is attempted to obtain a sufficient herbicidal effect simultaneously on different varieties of lawn grasses with the use of a single herbicide, phytotoxicity occurs to those varieties of lawn grasses which are poorly resistant. Hence, many types of herbicides are marketed and used according to the varieties of lawn grasses. In upland farms where crops, such as wheat, barley, rye and oats (hereinafter referred to as xe2x80x9cwheat and the likexe2x80x9d) and vegetables, are cultivated, annual weeds mainly occur repeatedly, so that many herbicides for their control are known.
In sowing seeds of a lawn grass to breed turf, early-stage weed control is important. This is because many of weeds developing on the turf occur throughout the year; thus, as the lawn grass grows, the growth of the weeds proceeds, and the effect of a herbicide tends to decline from the viewpoint of weed control. However, application of a herbicide before or after sowing of lawn grass seeds is apt to cause phytotoxicity. Currently, therefore, there is no choice but to apply a herbicide after lawn grass breeding.
Accordingly, a desire has been expressed for a herbicide which, used alone, can produce a sufficient herbicidal effect on many varieties of lawn grasses and crops, and which is safe for lawn grasses and crops such as vegetables without causing phytotoxicity even when applied before or after sowing of lawn grass seeds.
It is an object of the present invention to provide a herbicide composition which can achieve a sufficient herbicidal effect simultaneously on many varieties of lawn grasses and crops alone, and which is safe for lawn grasses without causing phytotoxicity even when applied before or after sowing of lawn grass seeds. It is also another object of the present invention to provide a method for sowing lawn grass seeds and breeding turf with the use of such a herbicide composition.
The inventors of the present invention have conducted extensive studies in an attempt to solve the above-described problems, and found that 1-(2-chlorobenzyl)-3-(1-methyl-1-phenylethyl)urea (hereinafter sometimes referred to as xe2x80x9ccumyluronxe2x80x9d) is highly safe, particularly, for lawn grasses, and shows an unsurpassed effect against annual bluegrass (Poa annua L.), flat-sedge (Cyperus microiria), etc., which are main turf weeds. They have also found that no phytotoxicity occurs even when cumyluron is applied before or after, or simultaneously with, sowing seeds of a lawn grass, such as ryegrasses (Lolium SPP.), to be seeded in breeding turf, and that no phytotoxicity occurs even when the above chemical is applied before or after, or simultaneously with, overseeding seeds of a lawn grass, such as ryegrass, onto an already bred turf.
In regard to weeds occurring in upland farms for cultivation of crops such as vegetables, cumyluron has also been found to exhibit a marked growth inhibiting effect on main weeds, including annual gramineous weeds such as annual bluegrass and foxtail, annual sedge weeds such as flat-sedge (Cyperus microiria), and perennial sedge weeds such as purple nutsedge (Cyperus rotundus) and Cyperus brevifolius, without causing phytotoxicity to wheat, etc. and vegetables.
Therefore, the present invention is a weed growth inhibitor composition for a lawn grass or an upland farm, which comprises cumyluron as an active ingredient.
The present invention is also a weed growth inhibitor composition for a lawn grass or an upland farm, which comprises an effective amount of cumyluron along with a carrier.
Moreover, the present invention is a method for inhibiting the growth of weeds, comprising application of a composition, which comprises an effective amount of cumyluron, to turf or an upland farm.
Furthermore, the present invention is a method for cultivation and management of a lawn grass, comprising application of a composition, which comprises an effective amount of cumyluron, before or after, or simultaneously with, overseeding lawn grass seeds to turf.
Cumyluron is a known compound disclosed in JP 60-72910 A/1985, JP 5-155710 A/1993, JP 5-155720 A/1993, JP 5-155721 A/1993, JP 5-255018 A/1993, JP 5-255022 A/1993, JP 5-294807 A/1993, JP 5-320011 A/1993, and JP 7-2602 A/1995. In these publications, cumyluron is disclosed only as an active ingredient of a herbicide composition for a paddy field, and its effectiveness as a weed growth inhibitor composition for a lawn grass and an upland farm, especially for a lawn grass, is neither suggested nor disclosed. Hence, a weed growth inhibitor composition for a lawn grass and an upland farm, containing cumyluron as an active ingredient, according to the present invention is novel.
In the present invention, the terms xe2x80x9cweed growth inhibitor compositionxe2x80x9d are interchangeable with the term xe2x80x9cherbicidexe2x80x9d.
The composition of the present invention contains a solid carrier and/or a liquid carrier, and can be present in various forms, such as granules, fine granules, wettable powder, water dispersible granules, emulsifiable concentrate, flowable (suspension concentrate), and dust, which are ordinary forms of agricultural chemicals when in use. For a lawn grass, the composition is often diluted about 1:100 to 1:1000 with water, and applied. Thus, a wettable powder, water dispersible granules, and a flowable are preferred.
The amount of cumyluron which is the active ingredient of the composition of the present invention is generally 0.5 to 95% by weight, preferably 1 to 70% by weight, more preferably 3 to 50% by weight, and most preferably 5 to 50% by weight based on the total weight of the composition, when in the form of granules or fine granules. For a wettable powder or water dispersible granules, the amount of cumyluron is generally 10 to 95% by weight, preferably 20 to 90% by weight, more preferably 30 to 85% by weight, and most preferably 50 to 80% by weight. For a flowable, the amount of cumyluron is generally 1 to 70% by weight, preferably 5 to 65% by weight, more preferably 20 to 60% by weight, and most preferably 30 to 55% by weight.
Examples of the solid carrier include mineral powders such as calcium carbonate, apatite, gypsum, silica gel, vermiculite, mica, diatomaceous earth, talc, pyrophyllite, acid clay, kaolin clay, silica clay, kaolinite, montmorillonite, bentonite, white carbon and pumice powder, plant powders such as microcrystalline cellulose and starch, and polymeric compounds such as polyvinyl chloride, xanthan gum and petroleum resin.
Examples of the liquid carrier include alcohols such as methanol, ethanol, cyclohexanol, amyl alcohol and ethylene glycol, aromatic hydrocarbons such as xylene and methyl naphthalene, halogenated hydrocarbons such as chlorobenzene and trichloroethylene, ethers such as ethyl cellosolve, butyl cellosolve and dioxane, esters such as isopropyl acetate and benzyl acetate, polar solvents such as dimethyl sulfoxide, kerosine, mineral oil, and water.
If necessary, stabilizers or adjuvants in customary use for agricultural chemicals, such as surface active agents, spreaders, and binders, may be formulated, whereby the reliability of the weed growth inhibiting effect can be enhanced.
The weed growth inhibitor composition of the present invention may, if desired, contain an insecticide, a fungicide, a plant growth regulator, a fertilizer, or other herbicide, or can be used in combination with these agents.
The weed growth inhibitor composition of the present invention can be made into a desired form by mixing cumyluron and the above-described carrier and/or the adjuvant or stabilizer, followed by dispersion, suspension, emulsion, granulation, grinding or the like in the customary manner.
The present invention also relates to a method for inhibiting the growth of weeds, comprising application of a composition, which comprises an effective amount of cumyluron, to turf or an upland farm.
The weed growth inhibitor composition of the present invention can be used, as such or diluted, when applied. The amount of application varies according to the scene of application, the time of application, the method of application, the weed targeted, etc. However, the amount of cumyluron applied is generally 50 to 3000 g, preferably 100 to 2000 g, more preferably 200 to 1500 g, most preferably 300 to 1000 g, for 1,000 m2.
For application, the granules, fine granules, or dust can be applied manually as such, or applied by a broadcaster, a power sprayer/spreader or the like. The wettable powder, water dispersible granules, emulsifiable concentrate, or flowable can be diluted with water, and applied by a sprayer, a watering pot or the like.
The application of the weed growth inhibitor composition of the present invention to an upland farm may be performed onto the soil surface after or before sowing seeds or transplanting tubers, seedlings or the like of a crop. Alternatively, the weed growth inhibitor composition can be applied to the surface of the soil, and incorporated into the soil by a tractor, a tiller, a hand spade or the like, before sowing or transplanting.
The composition of the present invention shows an unsurpassed effect against annual gramineous weeds such as annual bluegrass, and annual sedge weeds such as flat-sedge when it is applied from before germination of the weeds until the initial stage of the germination, and potently suppresses the growth of perennial sedge weeds such as purple nutsedge and Cyperus brevifolius. The composition of the present invention also has a long-term residual effect.
The xe2x80x9cupland farmxe2x80x9d in the present invention refers to upland farming agricultural lands and arable lands for cultivating wheat and the like, peas, Chinese cabbage of Shantung type, tomatoes, lettuce, spinach, carrots, Japanese radish, onions, welsh onion, potatoes, corn, etc., and excludes paddy fields. The weed growth inhibitor composition of the present invention has very high safety, particularly, for wheat, peas, Chinese cabbage of Shantung type, tomatoes, lettuce, spinach, carrots, Japanese radish, and onions.
The xe2x80x9clawn grassxe2x80x9d herein refers to both of Japanese type lawn grasses and American or European lawn grasses. Examples of the Japanese type lawn grasses include South Japanese lawngrass (Zoysia matrella) and Japanese lawngrass (Zoysia japonica). Examples of the American or European lawn grasses include ryegrasses, Kentucky bluegrass (Poa pratensis), bentgrasses (Agrostis L.), and tall fescue (Festuca arundinacea). The weed growth inhibitor composition of the present invention is highly safe for lawn grasses, and causes minimal phytotoxicity to both the Japanese type lawn grasses and the American or European lawn grasses. In a golf course, this composition can be used safely in turf including the putting green.
The present invention also relates to a method for cultivation and management of a lawn grass, comprising application of the composition of the present invention before or after, or simultaneously with, overseeding lawn grass seeds to turf.
Techniques for breeding a new lawn grass by overseeding of a reared turf have already been established. For example, South Japanese lawngrass, a Japanese type lawn grass, stops growing in the autumn, and has leaves in the aerial part withered. Thus, seeding with an American or European lawn grass in the autumn to maintain green turf even after autumn is a technique used in many golf courses. Moreover, overseeding with a new variety of lawn grass seeds or the same variety of lawn grass seeds for lawn renewal is used as an ordinary way of turf management.
Under these circumstances, the weed growth inhibitor composition of the present invention can be applied before or after sowing of lawn grass seeds (from before germination until the initial stage of germination), or simultaneously with their sowing, and causes no phytotoxicity to an already bred turf or to a newly seeded turf. That is, it is a weed growth inhibitor composition which can control weeds noxious to a lawn and breed and manage turf, and which is suitable, particularly, for turf.
The following Preparation Examples and Test Examples are provided in order to further illustrate the present invention but should not be construed as limiting the scope thereof. In the Examples, xe2x80x9cpartsxe2x80x9d mean parts by weight.